21055527 has 12 divisors (see below), whose sum is σ = 30597840. Its totient is φ = 13951968.

The previous prime is 21055513. The next prime is 21055543. The reversal of 21055527 is 72555012.

It is a happy number.

21055527 is a `hidden beast` number, since 2 + 105 + 552 + 7 = 666.

It is not a de Polignac number, because 21055527 - 2⁷ = 21055399 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21055527.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21050527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5502 + ... + 8507.

It is an arithmetic number, because the mean of its divisors is an integer number (2549820).

Almost surely, 2^21055527 is an apocalyptic number.

21055527 is a deficient number, since it is larger than the sum of its proper divisors (9542313).

21055527 is a wasteful number, since it uses less digits than its factorization.

21055527 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14182 (or 14179 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 21055527 is about 4588.6301877576. The cubic root of 21055527 is about 276.1353699520.

The spelling of 21055527 in words is "twenty-one million, fifty-five thousand, five hundred twenty-seven".